PHL145H5 Lecture 2: Arguments
Document Summary
Recall: in this course we want to learn to reason better. Practice & get better at reasoning well and avoiding reasoning poorly. An argument is: a group of one or more claims used to support (reasons, one further claim. The conclusion is: the claim being supported. The premises are: the claims used to support the conclusion. A deductively valid argument is one such that: If (hypothetically) all of its premises are true, then its conclusion must be true. This definition does not require that either the premises or the conclusion of a valid argument be true. This definition does not say anything about what happens if one or more of the premises is false. This definition does not say that if any of the premises are false, then the conclusion must be false. This definition does not say anything about what happens if the conclusion is true.
